The TBB-1B is an in-line device that actively boosts talk battery power to analog devices. Use the TBB-1B to boost talk battery from a VoIP phone system ATA with an FXS port, an analog PABX extension, a VoIP cable modem, a POTS line and more. The incoming under powered line is connected to the TBB-1B where talk battery voltage is boosted to 48V DC. The line with boosted talk battery now travels from the TBB-1B to the analog device. Analog devices that can benefit from the use of the TBB-1B include elevator phones, emergency and area of refuge phones, alarm panels, door entry phones and traditional analog telephones.
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